Portable disk abrading machine



Aug. 5, .1941.

A. N. EMMONS PORTABLE DISK ABRADING MACHINE Filed July 24, 1957 4 SheetsSheet l A. N. EMMONS 2,251,442-

IORTABLE DISK ABRADING MACHINE Filed July 24, 1 957 4 Sheets-Sheet 2 l/ I NVENTOR. Q O 66 afar/MW ATTORNEYS.

Aug. 5, 1941. H A. N. EMMONS Z PORTABLE DISK ABRADING MACHINE Filed July 24, 1957 4 Sheets-Sheet 5 ATTORNEYS;

g-. 1941 A. N. EMMONS 2,251,442

PORTABLE DISK ABRADING' MACHINE Filed July 24, 1957 4 Sheets-Sheet 4 INVENTOR.

ATTORNEYS;

Patented Aug. 5, 1941 ,UNlTED res rarsur FlCE ' 2,251,442 PORTABLE DISK ABRADIN G MACHINE Arthur N. Emmons, Nedrow, N. Y., assignor to The Porter-Cable Machine Company Inc., Syracusa'N. Y., a corporation of New York Application July 24, 1937, Serial No. 155,5t7 3 Claims. (01. 51-177) inafter set forth and claimed.

In describing this invention, reference is had to the accompanying drawings in which like characters designate corresponding parts in all the views.

Figure l is a front elevational view of the machine embodying my invention.

Figure 2 is a front elevational view of the machine shown in Figure 1 arranged in inverted position.

Figure 3 is a vertical sectional view of the machine.

Figure 4 is a bottom plan view of the machine.

Figure 5 is a bottom plan view of the lower end section of the machine with the abrading disk and dust bafrle removed.

Figure 6 is a view taken on line $t, Figure 3, with the suction fan removed.

Figure '7 is a view taken on line 'l-l, Figure 3.

The embodiment of the invention, as here shown, consists of a substantially cylindrical casing [0 open at each end and formed or provided with a partition l|.- The upper end portion of the casing It, above the partition ll, constitutes a fan chamber l2, and the lower portion of the casing forms a motor chamber in which the field B3 of the motor is mounted and secured by means of screws 15.

The machine further includes a lower end or base section It detachably secured to the lower end of the casing has by screws ll. The upper side of the base I6 is provided with an upwardly extending annular flange l8 which extends into the open end of the casing and aids in maintaining the base and casing in predetermined axial relationship.

The base is formed with a gear compartment 28 in which are arranged gears constituting the motion transmitting means between the motor and the abrading disk. The gear compartment 2E! opens through the bottom end of the base, and the opening is provided with a closure in the nature of a cap 2| detachably secured to the base as by screws 22 threading into holes 23, see Figure 5. The cap 2! and base 16 are provided with axially alined apertures to receive anti-friction bearings 24 in which a stub shaft 25 g is journalled. The base It and the partition ll in the casing Id are also formed with axially alined apertures to receive anti-friction bearings in which armature shaft 26 is journalled. The lower end of the armature shaft 26 extends into the gear compartment 28, and a pinion 21 is mounted thereon and arranged to mesh with gear 28 secured on the stub shaft 25. The stub shaft 25 extends outwardly or downwardly through the cap 2 i, and a suitable disk is secured thereto, and on the face of which is secured an abrasive sheet 38 which may be removed or renewed by removal of the screw 3| threading into the end of the shaft 25.

The casing It is also provided with inwardly extending bosses 33 arranged in diametrical rela- 5 tends upwardly through the partition ll into the fan chamber 12, and a fan 36 is mounted thereon. The rear side wall of the chamber I2 is formed with a discharge opening 31 communicating with a shortconduit 38 on which is detachably secured a dust collecting bag 39, as by ring it. The upper end of the casing or fan chamber is closed by a dis'coidal closure or plate ll detachably secured to the casing as by screws 42. The plate 4! is provided with an annular recess adjacent its periphery in which is mounted a ring 43 of yielding material, such as rubber.

The general arrangement and relationship of the machine is such that it may be inverted and supported on the plate M, as indicated in Figure 2; It will be understood that the sheets of face would be considerably marred during the V changing operation. This is avoided by the rubber ring 3, and due to the comparatively large diameter of the plate 41 and the balanced arrangement of the machine, it is entirely stable in inverted position.

The flange M5 on the upper side of the base l6 extends inwardly adjacent the periphery of a fan 4'6 secured to the lower end of armature shaft 28, and the flange i8 is provided with a discharge opening 4?. The casing I is formed with a plurality of openings 48 immediately beneath the partition l2, and while the motor is in operation, the fan 56 draws air inwardly through the openings 48, downwardly around the field and armature of the motor, and outwardly through the discharge opening 4?.

In order that the machine may be conveniently used in poorly lighted places, it is equipped with a lamp arranged to direct its rays downwardly and forwardly in front of the cutting portion of the abrading disk. As here shown, a lamp receptacle B is secured to the front side of the casing l0 adjacent the lower end thereof, and the receptacle and lamp 5i are enclosed by a housing 52 detachably secured to the front of the casing as by screws 53, the lower end of the housing being provided with an opening 54 to permit the rays from the lamp 5! to be directed upon the work being finished. The outlet opening 41 of the chamber enclosing fan 46 is arranged adjacent lamp 5i, and the air is also discharged through the light opening 54 of the lamp housing 52. This arrangement provides for the circulation of clean air around the lamp 5|, and prevents the collection and accumulation of fine dust rising from the abrading disk, settling on the lamp and decreasing its efllciency. The lamp 51 is controlled by a small switch 56 located in the base portion of one of the handles 51 secured on either side of the casing It and extending rearwardly for convenient manipulation of the machine.

The base it is formed with a depending annular flange 69 of substantially arcuate formation and which extends around the major portion of the periphery of the abrading disk, and the ends 6| extend inwardly in close proximity to the periphery of the disk, see Figure 4. The lower edge of the flange 60 extends in angular relationship to the axis of the machine. That is, downwardly and rearwardly, as indicated at 62, Figure 3. The portion of the abrading disk extending forwardly from the flange 6| constitutes the cutting portion of the disk. That is, the portion which is in contact with the surface being finished during the finishing operation. This requires a slight tilting forward of the machine, and the angular arrangement of the lower edge of the flange G0 maintains the flange in close proximity to the surface being finished during the finishing operation. The base 5 may be provided with casters 64 movably mounted in housings 65 secured to bosses 66 formed on the rear side portions of the base.

The flange 6! forms a dust collecting chamber about the abrading disk, and the rear portion of this chamber extends upwardly on each side of a rib 68 and communicates with arcuate openings 69 extending through the upper side of the base, see Figure 5. The dust collecting chamber and the arcuate opening 69 are connected with the fan chamber I2 by means of arcuate extending ducts 10 formed in the rear side wall of the casing Hi and connecting at their upper ends with an arcuate chamber H extending upwardly and inwardly toward the armature shaft and communicating with a central opening 12 in the bottom of the fan chamber l2, see Figure 6.

When the machine is in operation, the fan 36 creates a partial vacuum in chamber H, ducts l0, and the lower dust collecting chamber and the dust created by the abrading disk and discharged within the flange 60 is drawn upwardly and discharged through the opening 31 into the bag 39. This general arrangement also serves the dual purpose of materially aiding in cooling the motor inasmuch as the ducts 10 are arranged in heat conducting relationship to the fleld of the motor.

Preferably, the cap 2| is provided with a radially extending flange 15 also of arcuate formation and which extends radially from the periphery of the abrading disk toward the casing or flange 6D, and terminates in relatively close proximity thereto to form a restricted opening 16. This arrangement intensifies the vacuum created by fan 36, and eifects a more rapid and complete collection of the dust as it is discharged from the abrading disk. Preferably, the flange I5 is arranged relatively close to the plane of the abrasive sheet 30, as shown in Figure 3. Also, the machine may be provided with a discoidal guard 11 fixedly secured to the base [6 or cap 2| by screws 18.

It will be observed that the structure described is particularly compact and rigid, and that the dust collecting system is particularly efficient in that while the discharge opening 31 is arranged adjacent the top of the machine permitting a convenient location for the attachment of bag 39, the dust travels a minimum distance and is effectively gathered up and discharged into the bag 39.

What I claim is:

1. A portable hand manipulated disk sanding machine comprising a substantially cylindrical casing, the lower end of said casing being formed with a depending arcuate wall, an abrading disk journalled in the lower end of the casing with the periphery of said disk arranged in spaced apart relationship to said wall, an arcuate housing overlying said disk and being detachably secured to the lower end of said casing, said housing being formed with a radial flange extending from the periphery of said disk toward said arcuate wall and terminating in spaced apart relationship thereto, suction means arranged in the casing and having an inlet opening in the lower end of the casing above said housing, a motor mounted in the casing, and motion transmitting means operatively connecting said motor and abrading disk.

2. A portable hand manipulated disk sanding machine comprising a cylindrical casing provided at its lower end with a gear compartment, a motor mounted in the casing with the rotor shaft extending into said compartment, a shaft journalled in the lower end of the casing and having one end extending through the bottom of the casing, an abrading disk mounted on the extending end of said shaft, gearing arranged in said gear compartment and operatively connecting the motor shaft and said second shaft, a cap detachably secured to the bottom of the casing and forming a closure for said gear compartment, said cap extending radially over the top of said disk and forming a housing therefor and being provided on its periphery with a radially extending flange terminating in spaced apart relationship from the periphery of the casing, suction means carried by the casing and having an inlet opening in the lower end of the casing above said flange.

3. A portable hand manipulated disk sanding machine comprising a substantially cylindrical casing, an abrading disk journalled in the lower end of the casing on an axis to one side of the form a comparatively narrow arcuate slot extending adjacent the periphery of the casing, suction means arranged in the casing and having an inlet opening connected with said slot, a motor mounted in the casing, and motion transmitting means operatively connecting the motor with said disk.

ARTHUR. N. EMMONS. 

